Endoscopes have been used in medical procedures for many years. Relatively recent developments in the field of fiber optics have allowed endoscopic devices to be developed for a wide range of medical applications. Also, advances in materials have resulted in devices that can be disposable and more economical.
In addition to procedures such as examinations of a patient, endoscopes have been employed to assist with procedures such as endotracheal intubation.
During an endotracheal intubation procedure, a flexible plastic endotracheal breathing tube is inserted into a patient's trachea for providing oxygen or anesthetic gases to the lungs. Usually, the endotracheal tube is introduced into the patient's trachea after the patient has been sedated or has become unconscious. Typically, the patient is placed on his or her back, and the patient's chin is lifted in order to place the patient in the so-called "sniffing" position. When the head and neck of the patient are situated to achieve the proper position, the patient's tongue typically falls downward toward the roof of the patient's mouth. The endotracheal tube must be inserted past the patient's teeth and tongue and further past the epiglottis and vocal cords into the trachea. After the endotracheal tube is advanced past the vocal cords and into the patient's trachea, the distal end of the tube should be approximately 2 to 4 centimeters (about 1 to 2 inches) in front of the bifurcation of the trachea in order to ventilate both of the patient's lungs equally.
Another procedure for providing oxygen or anesthetic gases to the lungs by placing a breathing tube into a patient's trachea is called a tracheostomy. Instead of inserting the breathing tube through the patient's mouth, an incision is made in the base of the patient's neck above the sternum so that a tracheostomy tube can be inserted into the patient's trachea.
Proper initial placement of a breathing tube is vital to the well-being of the patient. While breathing tubes are most often used for a relatively short period of time such as for surgery or under emergency conditions, sometimes a breathing tube is required by a patient for an extended period. In these cases it is desirable to change the patient's endotracheal or tracheostomy tube approximately weekly to prevent harmful reaction from long-term intubation such as granulation tissue reaction, infection, or stenosis of the trachea, larynx, or subglottis.
In some cases, the placement of the tube is made difficult due to trauma or physical differences in the tracheal areas of different patients. Also, patients differ in size, age, and sex. Serious complications may result if the tube is placed incorrectly, such as into the esophagus or into only one bronchus. With an endoscopic intubation assist device, the practitioner can view the patient's tracheal area and is able to more accurately place the tube. Existing devices, however, are not adjustable for different size patients that require various sizes of endotracheal or tracheostomy tubes.
In some cases, an elongated wire or stylet made of malleable material which can be bent or shaped to accommodate a particular patient is used to assist intubation. The malleable stylet is inserted into the endotracheal tube and then used to guide the tube into place within the patient's tracheal passage. The stylet is then removed, and the tube is connected to a supply conduit which then supplies the oxygen or other gas to the lungs of the patient. In the normal practice of endotracheal intubation procedures, the medical practitioner pre-shapes a 3 to 4 mm outside diameter aluminum stylet over which the endotracheal tube is placed and then follows a blind approach to accomplish intubation.
Fiber optics may be incorporated into the stylet which is used to guide the tube into place. Examples of intubation assist devices which incorporate fiber optics are disclosed in Adair, U.S. Pat. No. 5,329,940 entitled "Endotracheal Tube Intubation Assist Device;" Salerno, U.S. Pat. No. 5,337,735 entitled "Fiber-Lighted Stylet;" Berci, U.S. Pat. No. 4,846,153 entitled "Intubating Video Endoscope;" and Zukowski, U.S. Pat. No. 3,677,262 entitled "Surgical Instrument Illuminating Endotracheal Tube Inserter."
One disadvantage of these types of devices is that while they provide some viewing, they can be used with an endotracheal tube of only one length or a limited range of lengths within a particular category such as pediatric or adult. Also, many of these devices are relatively complicated in that they may include a suction port, oxygen or gas supplying means, gas flow directed means, or other control systems.
The prior art patents described all disclose fixed length endoscopes that can only be used with endotracheal tubes of only one length or of a limited range of lengths. These devices necessitate different versions for the many available endotracheal tubes from pediatric to adult sizes. Also, prior art devices that use fiber optics are relatively expensive and complex and therefore are not used very often because of the high cost of operating and maintaining these devices. The cost of repairing or replacing one of these units is very high compared to the that of the present invention.
A need exists in the art for an intubation assist device that allows the medical practitioner to view the tracheal area during the procedure. A hand-held viewing system with a construction that is easily assembled and disassembled is preferable. It would also be beneficial to be able to use one size of endoscopic viewing system with several sizes of endotracheal tubes such as from pediatric to adult sizes. The device also should be simple, inexpensive, and easy to use. The present invention meets these desires.